The spasm anti-spam milter is a spam filter for sendmail 8.12+ (with libmilter support). Its current features include logging and quarantining of rejected spam, fully virtualised settings for domains, individual whitelists and blacklists, and over two dozen filters, which can be set individually on a per-domain or per-email address basis, including local (system) blacklist, rDNS resolution, HELO/EHLO verification, envelope sender address verification, numerous DNS-based lists, whitelist-only mode, and auto-blacklisting via spamtrap addresses and unknown user rejections.
